SANTA CRUZ - Commuters heading to work Tuesday were greeted with rubble and rebar where part of the La Fonda Avenue Bridge used to be, heralding a critical step in an ongoing highway widening project.

The bridge is being rebuilt as part of an $22 million overhaul between Morrissey Boulevard and Soquel Avenue, including the addition of exit lanes in both directions that could help ease what is ranked among the worst traffic congestion in the Bay Area.

The work went off without a hitch, with more expected overnight. The bridge over the northbound lanes comes down next week.

"It's going really well," said Karena Pushnik, a spokeswoman for the county's Regional Transportation Commission, which is managing the project.

Pushnik was among a small group of onlookers who came out to watch the overnight work, which involved cutting the bridge in place and using an excavator to knock it down.

The concrete will be crushed on site and used as aggregate, with the rebar recycled elsewhere. The new bridge will include sidewalks and bike lanes in both directions, and will take six to eight months to complete.

Southbound Highway 1 was closed while the work took place. Northbound lanes will be closed Monday and Tuesday from 11 p.m. to 4 a.m., and Pushnik said the California Highway Patrol redirected traffic Monday night without significant problems.

"No problem, very light traffic," she said.

Students at DeLaveaga Elementary School and Harbor High School will be affected when the bridge is out. The Transportation Commission has set up websites for each school to assist teachers, parents and students. Visit commutesolutions.org/delaveaga or commutesolutions.org/harbor for more information.

The project is not related to a nearby gas leak that closed Soquel Avenue for hours on Tuesday, adding another snarl to a woeful summer for local traffic.